The fight was stopped by the doctor after four rounds. Ortega’s left eye was almost closed, his face bloodied.

The skills of Holloway, who was returning from an injury-plagued year, were too much for Ortega, who had rallied in the third round but was unable to take Holloway down or use his vaunted jiu-jitsu.

UFC president Dana White applauded the decision to end the fight.

“That fifth round should never have happened and I’m glad it didn’t,” he said. “The fight needed to be stopped. For us all of in here that have been in the fight game for a long time, that’s what you call too tough for your own good.

“I believe he could have done the fifth round. I believe he would have done the fifth round. But it should have never happened … He’s a young talented guy and I think going into that fifth round would have been very bad for him health-wise. The fourth round wasn’t good for him health-wise.”

Holloway improved to 20-3-0, adding to his impressive credentials, while Ortega slipped to 14-1-0 with one no contest.

It could be Holloway’s last fight at 145 pounds. White wants him to move up to lightweight (155) to avoid the grueling weight cut.

Valentina Shevchenko, a native of Kyrgyzstan fighting out of Peru, overpowered a game, but outmatched Joanna Jedrzejczyk, of Poland, for the vacant women’s flyweight title in the co-main event. Shevchenko won a unanimous five-round decision.

Ortega, an accomplished Brazilian jiu-jitsu black belt, entered the arena to the sounds of DMX’s “X Gon’ Give It To Ya.” Holloway walked out to “Game Over” by Lil’ Flip and then “Hawaiian Kickboxer” by Moke Boy.

The crowd started chanting “Holloway, Holloway” as the two circled each other. Ortega scored with counter punches as the champion came forward and connected with an elbow. A relaxed Holloway began to find his striking distance and stuffed a takedown as the round ended.

Ortega’s nose began to bleed profusely in the second as Holloway fired punches. Another takedown was rebuffed and Holloway taunted Ortega. The two exchanged words after the round that was dominated by Holloway.

Ortega came back in the third, connected with punches and almost got Holloway to the ground. Holloway fought back with punishing blows as Ortega continued to bleed from the face.

When Ortega connected, Holloway nodded as if to give him props. Ortgea showed he can take a punch.

Holloway danced in the fourth and then hammered Ortega at the fence. He took him down later in the round.

The 27-year-old Holloway had won his last 12 fights since an August 2013 loss by decision to Conor McGregor.

It was Holloway’s first fight since Dec. 2, 2017, due to a variety of health issues.

The two 145-pounders were originally slated to meet at UFC 226 in July, but Holloway was forced to withdraw at the last minute due to what was thought to be “concussion-like symptoms.”

An ankle injury had forced Holloway out of a March bout against former lightweight champion Frankie Edgar at UFC 222. Ortega filled in for Holloway, winning by a spectacular first-round TKO.

Holloway also missed out on a short-notice fight with current lightweight champion Khabib Nurmagomedov at UFC 223 in April (after Tony Ferguson withdrew with a knee injury), pulling out during his weight cut.

The lone blemish on the 27-year-old Ortega’s record was a 2014 win over Mike de la Torre that was changed to a no contest after a positive test for the steroid drostanolone. The California native was suspended nine months and fined US$2,500.

Ortega apologized for the failed test, saying he took the drug to help with his weight cut.